Under Armour's Armour 39 fitness tracking system (pictures)

Under Armour is going after Nike's FuelBand and other fitness-monitoring systems with its own setup.

Read More

Under Armour's Armour 39 tracking system

Under Armour unveiled its Armour 39 system today, which includes a strap that monitors, among other things, your heart rate. The strap also has a slot for a "bug," which acts like a computer, sending data to the cloud via a Bluetooth connection.